I agree. But sadly, I don't think we can expect it to happen in the Sims 4. Because it's pretty close to impossible to integrate in the game at this point. Even if it were developed right now, it would ask so much time and budget, and it would be very likely to introduce many new graphical bugs (which have been more and more numerous lately, with City Living and the toddler patch). It would have been easier to implement before release of the base game.